I've found that having a dedicated room (I use my tiny closet as it's the only one I've got) and headphones have made a huge difference. Also, being selective about when my second screen is on (it can be very distracting in meetings) helps keep me kind of focused;
If you have a separate room, use it.
Invest in a good chair, your back will thank you.
Standing desks are cool, but I like big work surfaces even more.
Have cabinet space to keep your desk de-cluttered.
Get good lighting. if you have a window I like my desk perpendicular to the window (against a wall). I gaze to my side a lot to think and it's nice to view some scenery.
If you don't have a separate room, the living space is fine. I double dip my tv's sound system when I'm working, but I also get to live alone.
I feel that setting up a professional space with proper network connectivity is a must and one should definitely avoid working from bed. Also, never bargain in the context of the time, working from home doesn't give liberty to be late so work hours should be defined.
With that, having natural sunlight around with minimal distraction and disturbance would do wonders!